Method of interconnecting a load/unload ramp assembly with a base plate of a disk drive

ABSTRACT

The present invention is directed to a load/unload ramp assembly which is interconnectable with a base plate of a dynamic load/unload-type disk drive. The load/unload ramp assembly generally includes a load/unload ramp and at least one base plate attachment cantilever. A fastener shaft is directed past each of the base plate attachment cantilevers and into a fastener receptacle on the base plate. A fastener head simultaneously exerts a force on each of the base plate attachment cantilevers that are engaged by the head to deflect such base plate attachment cantilevers toward the base plate, to in turn dispose the load/unload ramp assembly in forcible engagement with the base plate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional of and claims priority under 35U.S.C. § 120 to U.S. patent application Ser. No. 10/027,907, now U.S.Pat. No. 6,927,943 that was filed on Dec. 21, 2001, and that is entitled“ATTACHMENT METHOD AND APPARATUS FOR LOAD/UNLOAD RAMP OF A DYNAMIC LOADDISK DRIVE”, and further claims priority from U.S. Patent ApplicationSer. No. 60/269,760, that was filed on Feb. 16, 2001, and that isentitled a “ATTACHMENT METHOD FOR LOAD/UNLOAD RAMP.” The entiredisclosures of both U.S. Patent Application Ser. No. 60/269,760 and U.S.patent application Ser. No. 10/027,907 are incorporated by referenceherein.

FIELD OF THE INVENTION

The present invention generally relates to dynamic load/unload-type diskdrives and, more particularly, to the manner of interconnecting aload/unload ramp with a base plate of the disk drive.

BACKGROUND OF THE INVENTION

Conventional dynamic load/unload-type disk drives typically include abase plate and a cover that is detachably connected to the base plate todefine a housing for various disk drive components. One or more datastorage disks are generally mounted on a spindle which is interconnectedwith the base plate and/or cover so as to allow the data storage disk(s)to rotate relative to both the base plate and cover via a spindle motor.An actuator arm assembly (e.g., a single rigid actuator arm, a pluralityof rigid actuator arms, an E-block with a plurality of rigid actuatorarm tips), is interconnected with the base plate and/or cover so as toallow the actuator arm assembly to move relative to both the base plateand cover in a controlled manner. This motion is either typically apivoting or a linear motion.

A suspension or load beam may be provided for each data storage surfaceof each data storage disk. Typically each disk has two of such surfaces.All suspensions are appropriately attached to and extend away from theactuator arm assembly in the general direction of the data storagedisk(s) during normal operations. A transducer, such as a read/writehead, is carried by a slider that is disposed on the free end of eachsuspension. Signals are exchanged between the head and the correspondingdata storage disk to read and/or write information. The position of theactuator arm assembly, and thereby each transducer, is controlled by avoice coil motor or the like which moves the actuator arm assembly todispose the head(s) at the desired radial position relative to thecorresponding data storage disk.

The head(s) of the disk drive is parked off its corresponding datastorage disk by using a load/unload ramp. The load/unload ramp istypically disposed at least toward (and possibly beyond) the perimeterof the corresponding data storage disk. Load/unload ramps may be madefrom plastic to reduce material costs, and are nonetheless attached tothe base plate. It is desirable to have the load/unload ramp demonstrategood wear characteristics as the suspension/slider moves along the ramp.Moreover, it is desirable for the load/unload ramp to tolerate theincreased temperatures that exist within the disk drive housing duringdisk drive operations. Certain plastics may have a tendency to creep atthese temperatures, particularly over those areas of the load/unloadramp that are stressed by the attachment of the load/unload ramp to thebase plate. “Creeping” refers to a progressive deformation over a periodof time due to a material being under a constant load or stress. Thistime dependent deformation has proven to be a limiting factor in theoperational integrity of at least certain designs of load/unload rampsthat are formed from plastic.

Creeping of a plastic load/unload ramp may have a number of undesiredeffects. For example, if the plastic load/unload ramp is attached to thebase plate using a screw, over time, creeping of the ramp plastic mayloosen the screw and result in the screw failing to adequately securethe load/unload ramp to the base plate. This problem has been addressedin a number of ways. A common practice to combat creeping has includedinsert-molding a metal plate into the plastic load/unload ramp toincrease the integrity of the attachment of the ramp to the base plate.However, this addition of a metal plate to the load/unload ramp can morethan double the cost of producing such ramps. Another attempt at solvingthe problem of creeping reflects using a screw in combination withlocking devices to attach the plastic load/unload ramp to the baseplate. However, locking devices such as thread locks not only add cost,but also add the risk of outgassing (i.e., the vaporization of materialsfrom one or more surfaces of the thread locks after they are placed inlow pressure environments during disk drive operations). Further,locking devices such as lock-washers add cost, create particulates, andmay require a more expensive grade of ramp plastic for compatible use.While suitable plastics with improved creep characteristics are known,they are significantly more expensive than even the attempted improvedattachment methods. Therefore, it would be desirable to have aload/unload ramp of a configuration that reduces manufacturing costs,provides a use-life that is greater than that of conventional ramps,and/or that reduces the effect of creep in relation to the attachment ofthe load/unload ramp to the base plate.

SUMMARY OF THE INVENTION

The present invention is generally directed to dynamic load/unload-typedisk drives. More specifically, the present invention is generallydirected to a load/unload ramp assembly for use with a compatible baseplate of a dynamic load/unload-type disk drive, which may utilize one ormore heads/data storage disks. That is, the present invention is equallyapplicable to single and multiple head disk drive configurations. Thedesign/configuration of the load/unload ramp assembly of the presentinvention desirably addresses the interconnection of the load/unloadramp assembly to the base plate in a manner that is not significantlyadversely affected by the elevated temperatures that exist within thedisk drive housing during disk drive operations. Accordingly, thedesign/configuration of any appropriate dynamic load/unload-type diskdrive may benefit from the installation of a load/unload ramp assemblyof the present invention in a manner that will now be described.

Generally, the present invention is embodied in a load/unload rampassembly that has at least one deflectable member that is deflectedtoward an underlying portion of a base plate to force the load/unloadramp assembly into engagement with the base plate. That is, any suchdeflectable member will initially be spaced from an underlying portionof the base plate, and then deflected toward the base plate to force theload/unload ramp assembly into engagement with the base plate.Typically, this deflection will be accomplished using one or moreappropriate fasteners. Any appropriate configuration may be used foreach deflectable member of the noted type. Therefore, although thepresent invention is hereafter described in relation to this deflectablemember being a “base plate attachment cantilever,” other types ofdeflectable members could be substituted therefore. For instance,another example of an appropriate configuration for a deflectable memberthat is encompassed by the present invention is a simple beam structurethat is supported at two spaced locations.

A first aspect of the present invention is embodied by a load/unloadramp assembly that is interconnectable with a base plate of a diskdrive. The load/unload ramp assembly generally has a ramp body thatincludes a load/unload ramp and at least one base plate attachmentcantilever that may be deflected at least generally toward the baseplate when engaged by at least one appropriate fastener. This deflectionof the base plate attachment cantilever(s) forcibly engages theload/unload ramp assembly with the base plate to appropriatelyinterconnect the same.

Various refinements exist regarding the features noted in relation tothe subject first aspect of the present invention. Additional featuresmay also be incorporated in the subject first aspect of the presentinvention as well. These refinements and additional features may existindividually or in any combination. The load/unload ramp assembly of thefirst aspect may be utilized with any base plate configuration thatallows the load/unload ramp assembly to be secured thereto by adeflection of at least one base plate attachment cantilever. Typically,each fastener that is used to secure the load/unload ramp assembly tothis base plate will have a corresponding fastener receptacle that isformed on a surface of the base plate that projects toward theload/unload ramp assembly when installed thereon. This base plate mayinclude a number of additional features, which will be discussed in moredetail below in relation to the second aspect.

Preferably, at least two base plate attachment cantilevers are utilizedby the first aspect, and such will be referred to as first and secondbase plate attachment cantilevers. Characteristics of these first andsecond base plate attachment cantilevers that are hereafter described inrelation to the first aspect may be utilized by each base plateattachment cantilever utilized by the first aspect, including where onlya single base plate attachment cantilever is utilized by the firstaspect. The first and second base plate attachment cantilevers mayextend at least generally toward each other or a common point, and haverespective first and second free ends. These first and second free endsmay be disposed in spaced relation to generally define at least aportion of a fastener aperture so that a shaft of a fastener can passby/between the first and second free ends. Additionally, the spacedrelation of the first and second free ends of the first and second baseplate attachment cantilevers makes it possible for the head of thefastener to simultaneously exert a force on the first and second baseplate attachment cantilevers. It should be appreciated that sideportions of the first and second base plate attachment cantilevers couldalso be disposed in space relation so as to allow a fastener to passtherebetween. In any case, upon the load/unload ramp assembly beinginstalled on the base plate and the head of a particular fastenerexerting a force on at least the first and second base plate attachmentcantilevers, these first and second base plate attachment cantileversare generally deflected toward the base plate to forcibly engage theload/unload ramp assembly with the base plate, and thereby to secure theload/unload ramp assembly to the base plate.

The first and second base plate attachment cantilevers that may beassociated with the first aspect may be generally disposed in opposingrelation. In other words, the first base plate attachment cantilever maybe positioned at or define a first portion of a fastener aperture, andthe second base plate attachment cantilever may be positioned at ordefine a second portion of this fastener aperture that is directlyopposite the first portion. The ramp body can have at least one apertureshelf positioned about the fastener aperture and recessed relative to anupper surface of each base plate attachment cantilever. Some variationsof the first aspect include both the first and second base plateattachment cantilevers and first and second aperture shelves. In suchvariations, the first and second base plate attachment cantilevers maybe positioned in opposing relation, and the first and second apertureshelves may be disposed in opposing relation. In one embodiment, areference line connecting the first and second base plate attachmentcantilevers is generally perpendicular to a reference line connectingthe first and second aperture shelves. Preferably, the intersectionpoint of these two reference lines generally corresponds with a centralportion of the fastener aperture of the load/unload ramp assembly.

Multiple base plate attachment cantilevers may be utilized in any mannerin relation to the first aspect (e.g., arranged in variety ofconfigurations). For instance, multiple base plate attachmentcantilevers may be utilized without collectively defining a fasteneraperture therebetween. For instance, each base plate attachmentcantilever could be deflected by its own fastener(s). That is, each baseplate attachment cantilever may have its own fastener or set offasteners. However and as noted above, a particular fastener maysimultaneously act on multiple base plate attachment cantilevers. Anycombination of base plate attachment cantilevers and fasteners may beused in relation to the first aspect. What is of importance is that anyfastener that is utilized by the first aspect to engage the load/unloadramp assembly against the base plate does so by deflecting one or morebase plate attachment cantilevers toward the base plate.

Any base plate attachment cantilever that is utilized by the firstaspect may be arranged in any appropriate fashion on the load/unloadramp assembly. For instance, a given base plate attachment cantilevermay be disposed interiorly of a perimeter of the load/unload rampassembly. Moreover, a given base plate attachment cantilever may bedisposed on a perimeter of the load/unload ramp assembly for deflectionby an appropriate fastener(s). The shaft of this fastener could extendthrough the load/unload ramp assembly, or could be disposed beyond theload/unload ramp assembly, so long as part of this fastener could stillengage at least one base plate attachment cantilever to deflect the samein the manner described herein.

Any of the base plate attachment cantilevers that may be associated withthe first aspect can each include one or more fastener head contactprotrusions or pads that are positioned on the upper surface of thecorresponding base plate attachment cantilever. In variations havingsuch fastener head contact protrusions, each fastener head contactprotrusion may be positioned at least generally at a free end of thecorresponding base plate attachment cantilever. In other words, since a“cantilever” generally refers to a projecting structure that is attachedor supported at only one end, each fastener head contact protrusion maybe generally disposed at an end of the respective attachment cantileverwhich is substantially free from attachment to and/or support from theramp body. However, it should be appreciated that any such fastener headcontact protrusion may be disposed anywhere on the corresponding baseplate attachment cantilever for engagement by the correspondingfastener(s). Preferably, a given base plate attachment cantilever has apair of the noted fastener head contact protrusions so as to “cradle”the head of the fastener that is engaged therewith to attach theload/unload ramp assembly to the disk drive base plate. In variations ofthis first aspect which include such fastener head contact protrusions,these fastener head contact protrusions are ideally positioned on thecorresponding base plate attachment cantilever so as to distribute theaxial force of the fastener to locations on the respective base plateattachment cantilevers that cause minimum physical distortion of theload/unload ramp assembly.

In one embodiment of the first aspect, a major axis of a given baseplate attachment cantilever is disposed at an angle relative tohorizontal prior to being engaged by the base plate attachment fastener.That is, the free end of a given base plate attachment cantilever may bedisposed at a higher elevation than its corresponding fixed end. Inaddition, a given base plate attachment cantilever may have a lowersurface that extends at least generally upwardly progressing toward itscorresponding free end. Stated another way, in one embodiment of thefirst aspect, an upper surface of a given base plate attachmentcantilever is disposed in non-parallel relation with a correspondinglower surface of the base plate attachment cantilever. Features, such asserrations or the like, may be formed on the lower surface of each baseplate cantilever to enhance the engagement with the underlying diskdrive base plate when attached thereto.

A second aspect of the present invention includes a disk drive having abase plate, a load/unload ramp assembly of the type discussed above inrelation to the first aspect, and at least one fastener that securesthis load/unload ramp assembly to the base plate. The base plategenerally has a first surface and preferably at least one boss (that is,a boss is not required by the second aspect). Each boss projects awayfrom the first surface, and at least one fastener receptacle is formedin the base plate (on/through a corresponding boss when utilized by thesecond aspect). A fastener is typically provided for each fastenerreceptacle and includes a head and a shaft. The shaft of each fastenerextends past at least one base plate attachment cantilever (for example,an end thereof; a side thereof) and is generally securely disposedwithin a corresponding fastener receptacle of the base plate.Accordingly, the head of each fastener exerts a force on at least onebase plate attachment cantilever to deflect each base plate attachmentcantilever engaged thereby toward the underlying base plate. Thisdeflection of each base plate attachment cantilever forces a bottomsurface of the load/unload ramp assembly into engagement with the firstsurface of the base plate to establish a secure interconnection betweenthe load/unload ramp assembly and the base plate.

Various refinements exist regarding the features noted in relation tothe subject second aspect of the present invention. Additional featuresmay also be incorporated in the subject second aspect of the presentinvention as well. These refinements and additional features may existindividually or in any combination. Initially, each of the variousfeatures discussed above in relation to the first aspect of the presentinvention of the load/unload ramp assembly may be incorporated into thissecond aspect of the invention as well, alone or in any combination.Additional features in relation to the base plate may also be utilizedby the second aspect. The base plate can include first and secondmounting pads disposed on the first surface of the base plate. Thesefirst and second mounting pads may be generally recessed relative to agiven boss of the base plate (i.e., disposed at a lower elevation). Inother words, a given boss of the base plate may extend out and away fromthe first surface of the base plate a greater distance than itscorresponding first and second mounting pads extend from the firstsurface of the base plate. In one embodiment, the first and secondmounting pads are disposed in opposing relation. In another embodiment,the first and second mounting pads may be positioned on the firstsurface of the base plate so that a given boss of the base plate ispositioned directly between the first and second mounting pads. In yetanother embodiment, the first and second mounting pads may be generallydisposed so that a reference line connecting the first and secondmounting pads is perpendicular to a reference line connecting first andsecond base plate attachment cantilevers that may be utilized by theload/unload ramp assembly in relation to the second aspect.

In variations of the second aspect in which the ramp body of theload/unload ramp assembly incorporates at least one aperture shelfpositioned about each fastener receptacle on the base plate, theaperture shelf/shelves preferably overlay(s) at least one of thecorresponding first and second mounting pads. While the apertureshelf/shelves are positioned about the corresponding fastenerreceptacle, some amount of clearance preferably exists between the shaftof the fastener (that also extends into the fastener receptacle) and thecorresponding aperture shelf/shelves. In other words, the head of agiven fastener preferably does not interface with the correspondingaperture shelf/shelves when the load/unload ramp assembly is in aninstalled position. However, embodiments are contemplated wherein oneboth of the head and the shaft of the fastener can interface with thecorresponding aperture shelf/shelves.

Ideally, the only contact between the first surface of the base plateand the bottom surface of the load/unload ramp assembly in the case ofthe second aspect (ignoring any contact via any alignment posts andcorresponding alignment holes that may be utilized and that arediscussed in more detail below) is between each mounting pad utilized bythe base plate and a corresponding portion of the bottom surface of theload/unload ramp assembly. In other words, excluding the contactexhibited via the alignment posts, the bottom surface of the load/unloadramp assembly is preferably free from direct contact with any otherportion of the first surface of the base plate other than the notedmounting pads.

In some variations of the second aspect of the present invention, thebase plate has at least one alignment hole. Preferably, the base platehas first and second alignment holes, with a given boss of the baseplate being positioned between the first and second alignment holes.Thus, the base plate can have first and second alignment holespositioned on opposite sides of a given boss of the base plate and firstand second mounting pads positioned on opposite sides of such a boss ofthe base plate, so that a first reference line connecting the first andsecond alignment holes is substantially perpendicular to a secondreference line connecting the first and second mounting pads.Preferably, the intersection point of these two lines generallycorresponds with a central portion of the fastener receptacle of thisboss of the base plate. The bottom surface of the load/unload rampassembly can have at least one alignment post configured to fit into thecomplimentarily shaped alignment hole(s) of the base plate. Thus, uponinstallation of the load/unload ramp assembly onto the base plate, thealignment post(s) of the load/unload assembly can be disposed within therespective alignment hole(s) of the base plate to prevent sliding and/orrotational movement of the load/unload ramp assembly in relation to thebase plate. Generally, each alignment post may have a circular,elliptical, or quadrilateral cross-sectional configuration, althoughother appropriate cross-sectional configurations are contemplated. Insome variations of the invention, the bottom surface of the load/unloadramp assembly can include the alignment hole(s), and the base plate caninclude the corresponding alignment pin(s). Any way of maintainingalignment of the load/unload ramp assembly on the base plate may beutilized.

The shaft of each fastener associated with the second aspect may bethreaded so as to be engaged with complimentarily threaded walls of thefastener receptacle of a given boss of the base plate. In oneembodiment, a given base plate attachment cantilever is sufficientlyspaced from a corresponding mounting boss and this boss is sufficientlysized such that the shaft of the fastener may be moved within thefastener receptacle to deflect the corresponding base plate attachmentcantilever(s) until the head of the fastener engages an upper surface ofthe corresponding boss. Stated another way, in an installed position,the head of a given fastener may have a lower surface which is seated onthe upper surface of a corresponding boss of the base plate, while atthe same time having engaged the corresponding base plate attachmentcantilever(s) so as to deflect the load/unload ramp assembly intoforcible engagement with the underlying base plate. In other words, onceinstalled, the lower surface of a given fastener head is in directcommunication/engagement with the upper surface of the correspondingboss of the base plate. This allows a given fastener to exert asignificant load on the base plate (by engaging a corresponding boss),while at the same time exerting a smaller (and more preferably asignificantly smaller) load on each of the base plate attachmentcantilevers that is engaged by the head of this fastener.

Any fastener associated with the second aspect and continuing with theforegoing (preferably via the lower surface of the head) may exert anaxial force within a range of about 25 pounds up to about 400 pounds,and more preferably about 100 pounds up to about 200 pounds, on theupper surface of the corresponding boss of the base plate. In additionto affecting a force on at least the upper surface of the correspondingboss, the lower surface of the fastener head generally deflects each ofthe base plate attachment cantilever(s) engaged thereby so as to disposethe load/unload ramp assembly into forcible engagement with underlyingportions of the first surface of the base plate as noted above. Thisdeflection of each of the base plate attachment cantilevers again isgenerally in response to the shaft of the corresponding fastener beingmoved further within the fastener receptacle and a resulting engagementof the head of the fastener against deflectable portions of the baseplate cantilevers that are associated with the particular fastener. Inone embodiment, in an installed position, each base plate attachmentcantilever generally deflects from about 4 mils to about 8 mils due tothe force exerted by the head of the fastener. However, embodiments arecontemplated in which the base plate attachment cantilever(s) exhibitdeflection levels which fall outside the range of about 4 mils to about8 mils. Generally, this axial force exerted on the base plate attachmentcantilever(s) of the load/unload ramp assembly may be within a range ofabout 1 pound up to about 10 pounds, and yet maintain a sufficientinterconnection between the load/unload ramp assembly and the baseplate. Variations of the subject second aspect are also contemplatedwhich exhibit axial forces outside the above-described ranges. Thus, theaxial force that is exerted on the boss of the base plate may begenerally greater, and preferably significantly greater, than the axialforce that is exerted on each of the base plate attachment cantilever(s)as noted above.

A third aspect of the present invention is embodied in a disk drivehaving a load/unload ramp assembly disposed on a base plate of the diskdrive. The load/unload ramp assembly has a ramp body that generallyincludes a load/unload ramp and at least one base plate attachmentcantilever. This base plate attachment cantilever can have a first fixedend and a first free end. The load/unload assembly is affixed to thebase plate of the disk drive utilizing at least one fastener having ahead and a shaft. The shaft of a particular fastener generally extendspast at least one base plate attachment cantilever of the load/unloadramp assembly and is securely disposed within a fastener receptacle ofthe base plate such that the head of the fastener exerts a force on anappropriate portion of the corresponding base plate attachmentcantilever(s) to deflect this base plate attachment cantilever(s) towardthe base plate, to in turn force a bottom surface of the load/unloadramp assembly into engagement with the base plate.

Various refinements exist regarding the features noted in relation tothe subject third aspect of the present invention. Additional featuresmay also be incorporated in the subject third aspect of the presentinvention as well. These refinements and additional features may existindividually or in any combination. Generally, each of the variousfeatures discussed in relation to any of the aspects of the presentinvention may be incorporated into this third aspect, alone or in anycombination.

A fourth aspect of the present invention is embodied by a method ofinterconnecting a load/unload ramp assembly with a base plate of a diskdrive. The method first includes disposing the load/unload ramp assemblyon the base plate. A shaft of a fastener engages at least one base plateattachment cantilever of the load/unload ramp assembly and is directedinto a fastener receptacle on the base plate. Prior to “loading” thebase plate cantilever(s) with the fastener, at least a portion of alower surface of each base plate attachment cantilever to be engaged bythis fastener is spaced from an underlying portion of the base plate.The method additionally includes moving the shaft of the fastenerfurther within the fastener receptacle and deflecting any base plateattachment cantilever engaged by the fastener such that a lower surfaceof the load/unload ramp assembly is directed into forcible engagementwith an underlying portion of the base plate.

Various refinements exist regarding the features noted in relation tothe subject fourth aspect of the present invention. Additional featuresmay also be incorporated in the subject fourth aspect of the presentinvention as well. These refinements and additional features may existindividually or in any combination. Generally, each of the variousfeatures discussed above in relation to the first, second, and thirdaspects of the present invention may be incorporated into this fourthaspect, alone or in any combination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of one embodiment of a disk drive with a coverplate having been removed.

FIG. 2 is a magnified perspective view of the disk drive of FIG. 1 withthe data storage disk removed.

FIG. 3 is a perspective view illustrating a top portion of theload/unload ramp assembly used by the disk drive of FIG. 1.

FIG. 4 is a perspective view showing a bottom portion of the load/unloadramp assembly used by the disk drive of FIG. 1.

FIG. 5 is a perspective view of a portion of the base plate used by thedisk drive of FIG. 1 and that is configured to receive the load/unloadramp assembly of FIGS. 3-4.

FIG. 6 is a top view of the load/unload ramp assembly of FIGS. 3-4,illustrating how the load/unload ramp assembly relates to mounting padsof the base plate of FIG. 5 that are positioned beneath the load/unloadramp assembly.

FIG. 7 is a cross-sectional view of the load/unload ramp assembly ofFIGS. 3-4 wherein mounted on the base plate of FIG. 5.

DETAILED DESCRIPTION

The present invention will now be described in relation to theaccompanying drawings, which at least assist in illustrating the variouspertinent features thereof. FIGS. 1 and 2 illustrate various componentsof one embodiment of a disk drive 10 that generally includes a baseplate 11 having a first surface 13. A cover (not shown) is typicallydisposed atop the base plate 11 and is detachably attached thereto todefine an enclosed space for the various disk drive components. The diskdrive 10 further includes a data storage disk 14 of any appropriatecomputer-readable data storage media. However, the data storage disk 14of disk drive 10 has been removed to show various other disk drivecomponents; accordingly, the data storage disk 14 is shown in dashedoutline only in FIG. 1, and is not illustrated in FIG. 2. This datastorage disk 14 is generally mounted on a spindle 16, which in turn isrotatably interconnected with the base plate 11 and/or cover of the diskdrive 10. Generally, the data storage disk 14 is made from glass,ceramic, or one or more of a variety of metals. A spindle motor 18 iscoupled to the spindle 16 to spin the data storage disk 14 at anappropriate rate.

The disk drive 10 also includes an actuator arm assembly 20 which pivotsabout a pivot bearing 22, which in turn is rotatably supported by thebase plate 11 of the disk drive 10 and/or cover. FIGS. 1 and 2illustrate that the actuator arm assembly 20 is positioned between thebase plate 11 and the data storage disk 14 (i.e., under the data storagedisk 14). This actuator arm assembly 20 generally includes a rigidactuator arm 24 which extends out from near the pivot bearing 22 and asuspension 26 attached to an end of the actuator arm 24 most remote fromthe pivot bearing 22. A head 28 is disposed at or near an end of eachsuspension 26. The head 28 typically includes a body (e.g., slider) andat least one transducer (not shown) that exchanges signals with thecorresponding data storage disk 14. The head 28 is interconnected withthe suspension 26 of the actuator arm assembly 20 so that the head 28generally faces away from the base plate 11 and toward the cover (notshown) of the disk drive 10. Stated another way, the head 28 ispositioned on the actuator arm assembly 20 in such a manner as to allowthe head 28 to operatively interface with a data storage surface of thedata storage disk 14 that faces the base plate 11. Accordingly, the diskdrive 10 also includes a load/unload ramp assembly 40 having aload/unload ramp 44 which slopes away from the data storage disk 14 andtoward the base plate 11 of the disk drive 10 so as to dispose the head28 and its corresponding data storage disk 14 in spaced relation whenthe head 28 is “parked” (i.e., at the termination of disk driveoperations). In the illustrated embodiment, the load/unload rampassembly 40 is disposed under the data storage disk 14 and at leastgenerally toward a radially inward portion thereof.

Additionally, a voice coil motor (VCM) 32 at least operativelyinterfaces with the actuator arm assembly 20 at a distal end 34 that isopposite that of the head 28. The VCM 32 imparts motion to the actuatorarm assembly 20, and thus to the head 28 (e.g. in response to a controlsignal). The VCM 32 generally consists of a magnet(s) and a coil of finewire, although other configurations are contemplated. Notwithstandingthe configuration of the disk drive 10 just described, the manner ofinterconnecting a load/unload ramp assembly with a base plate that willnow be discussed may be incorporated into any appropriate disk driveconfiguration.

FIGS. 3-4 illustrate further details of the load/unload ramp assembly 40that is interconnectable with the base plate 11 of the disk drive 10.The load/unload ramp assembly 40 is configured in a manner so as toallow the same to be fabricated from plastic, although other materialscould be utilized. Generally, the load/unload ramp assembly 40 has aramp body 42 that includes a load/unload ramp 44 which generally assistsin separating the head 28 from contact with the data storage disk 14when the head 28 is parked. Generally, as disk drive operations areterminated, the voice coil motor 32 pivots the actuator arm assembly 20so as to move the head 28 toward a radially inward location on itscorresponding data storage disk 14 (or at least generally toward thespindle 16). During this motion, the head 28 engages the load/unloadramp 44. Continued movement of the actuator arm assembly 20 in the noteddirection thereby directs the head 28 away from the data storage disk 14and at least generally toward the base plate 11 of the disk drive 10.Features may be incorporated into the load/unload ramp assembly 40 so asto attempt to retain the actuator arm assembly 20 in the parked positionuntil disk drive operations are subsequently re-initiated.

The load/unload ramp assembly 40 generally is configured to enhance oneor more aspects of its interconnection with the base plate 11. In thisregard, the load/unload ramp assembly 40 includes first and second baseplate attachment cantilevers 46, 48, respectively, which extend at leastgenerally toward each other and have respective first and second freeends 47, 49, and respective first and second fixed ends 51, 53. Anynumber of base plate attachment cantilevers may be utilized by theload/unload ramp assembly 40, including a single base plate attachmentcantilever and more than two base plate attachment cantilevers. Eachrespective fixed end 51, 53 is in direct contact with the ramp body 42.In other words, the fixed end (e.g. 51, 53) of each base plateattachment cantilever 46, 48 is in uninterrupted engagement with theramp body 42. Conversely, the respective first and second free ends 47,49 of the base plate attachment cantilevers 46, 48 are disposed onrespective opposite ends of the respective attachment cantilevers 46,48. In other words, the first fixed end 51 of the first base plateattachment cantilever 46 is disposed at an end of the cantilever 46adjacent the ramp body 42; while the first free end of the first baseplate attachment cantilever 46 is disposed at an end opposite that ofthe first fixed end 51 and most remote from any attachment to the firstbase plate cantilever 46. Similarly, the second fixed end 53 of thesecond base plate attachment cantilever 48 is disposed at an end of thecantilever 48 adjacent the ramp body 42; while the second free end ofthe second base plate attachment cantilever 48 is disposed at an endopposite that of the second fixed end 53 and most remote from anyattachment to the second base plate cantilever 48.

The first and second free ends 47, 49 of the first and second base plateattachment cantilevers 46, 48, respectively, are disposed in spacedrelation to generally define a fastener aperture 50. This fasteneraperture 50 provides a space so that a shaft 54 of a fastener 52 canpass between the first and second free ends 47, 49 of the first andsecond base plate attachment cantilevers 46, 48, respectively and intothe base plate 11. In other words, the fastener aperture 50 is generallyan open area, at least part of which is defined between the first andsecond base plate attachment cantilevers 46, 48. The first and secondfree ends 47, 49 of the first and second base plate attachmentcantilevers 46, 48 are spaced apart a defined distance that enables theshaft 54 (shown in FIG. 7) of the fastener 52 to pass through the atleast generally round fastener aperture 50, and yet that enables a head56 of the fastener 52 to “catch” on or at least otherwise engage thefirst and second base plate attachment cantilevers 46, 48, preferably ator near at least their first and second free ends 47, 49, respectively,to exert a downwardly-directed force (or at least generally toward thebase plate 11) on the first and second base plate attachment cantilevers46, 48. The first and second base plate attachment cantilevers 46, 48are disposed in opposing relation so that the first base plateattachment cantilever 46 is positioned on a side of the fasteneraperture 50, and the second base plate attachment cantilever 48 ispositioned on anther side of the fastener aperture 50 opposite the firstbase plate attachment cantilever 46.

The first and second base plate attachment cantilevers 46, 48 each havea pair of fastener head contact protrusions 76 positioned on an uppersurface 66, 68 of each of the first and second base plate attachmentcantilevers 46, 48, respectively. These fastener head contactprotrusions 76 are positioned at least generally at the respective firstand second free ends 47, 49, respectively, of each of the first andsecond base plate attachment cantilevers 46, 48. Each fastener headcontact protrusion 76 at least generally projects out and extends awayfrom adjacent portions of the respective upper surface 66, 68 of thefirst and second base plate attachment cantilevers 46, 48. These contactprotrusions 76 are illustrated as having an oblong/elliptical-typecross-sectional configuration; however other cross-sectionalconfigurations (e.g., circular, triangular, quadrilateral) will beobvious to those of ordinary skill in the art. In an installed position,a lower surface 57 of the head 56 of the fastener 52 generally engagesthe fastener head contact protrusions 76 and avoids contact with theremainder of the upper surfaces 66, 68 of the first and second baseplate attachment cantilevers 46, 48. The protrusions 76 on each baseplate attachment cavalier 46, 48 are spaced such that they engage thehead 56 of the fastener 52 at two displaced locations. However, otherembodiments may have only one contact protrusion 76 on each of the firstand second base plate attachment cantilevers 46, 48. In suchembodiments, the contact protrusion could occupy entire free end (e.g.47, 49) of each of the respective first and second base plate attachmentcantilevers 46, 48. Other embodiments could have more than two contactprotrusions 76 on each of the first and second base plate attachmentcantilevers 46, 48. Yet other embodiments could have first and secondbase plate attachment cantilevers 46, 48 which are free of any fastenerhead contact protrusions 76. In such embodiments, in an installedposition, a lower surface 57 of the head 56 of the fastener 52 woulddirectly engage the first and second upper surfaces 66, 68 of therespective first and second base plate attachment cantilevers 46, 48.

In addition to the first and second upper surfaces 66, 68, the first andsecond base plate attachment cantilevers 46, 48 have respective firstand second lower surfaces 78, 80. These lower surfaces 78, 80 areillustrated as being disposed in non-parallel relation to theircorresponding upper surface 66, 68, respectively to define awedge-shaped profile or the like for the first and second base plateattachment cantilevers 46, 48. That is, the thickness of the first andsecond base plate attachment cantilevers 46, 48 at their respective freeends 47, 49 is less than the thickness of the cantilevers 46, 48 attheir respective fixed ends 51, 53. Other configurations may be utilizedfor the first and second base plate attachment cantilevers 46, 48.Moreover, in one embodiment the major axis of the cantilevers 46, 48 isdisposed at an angle to the horizontal prior to engaging the fastener 52against the cantilevers 46, 48. That is, in an undeflected state and inone embodiment, the free ends 47, 49 of the cantilevers 46, 48 aredisposed at a higher elevation and their corresponding fixed end 51, 53.Other “static” profiles could be utilized for the cantilevers 46, 48.The ramp body 42 also has first and second aperture shelves 62, 64,respectively, positioned about the fastener aperture 50 and recessedrelative to upper surfaces 66, 68, respectively, of each of the firstand second base plate attachment cantilevers 46, 48. In other words, inan installed position, the distance between first and second apertureshelves 62, 64 and a reference plane in which the base plate 11 at leastgenerally extends is less than the distance between the upper surfaces66, 68 of the first and second base plate attachment cantilevers 46, 48and this reference plane. As with the first and second base plateattachment cantilevers 46, 48, the first and second aperture shelves 66,68 are disposed in opposing relation. These aperture shelves 66, 68 aregenerally arcuately-shaped/concave and define at least a portion of thefastener aperture 50 of the ramp body 42 as well. In particular andreferring to FIG. 6, a first reference line 70 connecting the first andsecond base plate attachment cantilevers 46, 48 is generallyperpendicular to a second reference line 72 connecting the first andsecond aperture shelves 47, 49. An intersection point 74 of these tworeference lines 70, 72 generally corresponds with a central portion ofthe fastener aperture 50 of the load/unload ramp assembly 40. It shouldbe appreciated that the load/unload ramp assembly 40 may be in currentlyformed or of one-piece construction. In one embodiment, the load/unloadramp assembly 40 may be formed by injection molding techniques utilizinga suitable plastic, such as acetal or liquid crystal polymer (LCP).However, other manufacturing techniques and/or materials could beutilized in relation to the load/unload ramp assembly 40.

Referring to FIGS. 5-6, the first surface 13 of the base plate 11 of thedisk drive 10 includes a boss 82 which projects away from the firstsurface 13 and which includes a fastener receptacle 84 for the fastener52. Generally, this boss 82 is preferably integral with the base plate11. In other words, the base plate 11 and the boss 82 are preferably aone-piece unit, as is the entirety of the base plate 11 (e.g., formed bycasting and/or machining such that there are no joints in the base plate11). The fastener receptacle 84 of the boss 82 generally has threadedwalls 94 designed to cooperatively engage the threaded shaft 54 of thefastener 52 upon insertion of the fastener 52 into the fastenerreceptacle 84 (see FIG. 7). The base plate 11 also includes first andsecond mounting pads 86, 88 disposed in opposing relation on the firstsurface 13 of the base plate 11, with the boss 82 being positionedbetween the first and second mounting pads 86, 88. Thus, a referenceline 73 connecting the first and second mounting pads 86, 88 generallyextends through the boss 82 of the base plate 11. The first and secondmounting pads 86, 88 are recessed relative to the upper surface of theboss 82 of the base plate 11. In other words, the upper surface of theboss 82 of the base plate 11 extends out and away from the first surface13 of the base plate 11 a greater distance than the first and secondmounting pads 86, 88 extend from the base plate 11. These first andsecond mounting pads 86, 88 are generally designed to stabilize theload/unload ramp assembly 40 when installed on the base plate 11 and/orto minimize the couple created by the force of the fastener 52 which cancontribute to bending/deformation of the ramp body 42 and, in turn,displacement of the ramp 44. Thus, the first and second mounting padsare positioned on the first surface 13 of the base plate 11 so that theyabut the boss 82 of the base plate 11. Accordingly, the first and secondmounting pads 86, 88 are disposed about the boss 82 of the base plate 11so that the reference line 72 passing through the first and secondmounting pads 86, 88 is perpendicular to the reference line 70connecting the first and second base plate attachment cantilevers 46, 48of the load/unload ramp assembly 40; thus, upon installation of theload/unload ramp assembly 40 onto the base plate 11, the apertureshelves 62, 64 overlay at least portions of the first and secondmounting pads 86, 88. Accordingly, when the load/unload assembly 40 isinstalled on the first surface 13 of the base plate 11, the bottomsurface 43 of the load/unload ramp assembly found underneath theaperture shelves 62, 64 will be pressed against the mounting pads 86, 88to prevent the ramp body 42 from bending to an undesired degree wheninstalling the load/unload ramp assembly 40 onto the base plate 11.

The base plate 11 also has first and second alignment holes 81, 83, withthe boss 82 of the base plate 11 being positioned between the first andsecond alignment holes 81, 83. Thus, the base plate 11 has first andsecond alignment holes 81, 83 positioned on opposite sides of the boss82 of the base plate 11 and first and second mounting pads 86, 88positioned on opposite sides of the boss 82 of the base plate 11, sothat a reference line 71 connecting the first and second alignment holes81, 83 is substantially perpendicular to another reference line 73connecting the first and second mounting pads 86, 88. Preferably, theintersection point 75 of these two lines 71, 73 generally correspondswith a central portion of the fastener receptacle 84 of the boss 82 ofthe base plate 11. Other locations may be appropriate for the alignmentholes 81, 83.

Referring back to FIG. 4, the bottom surface 43 of the load/unload rampassembly 40 has first and second alignment posts 90, 92 configured tofit into the respective first and second alignment holes 81, 83 of thebase plate 11 illustrated in FIG. 5. Generally, the first and secondalignment posts 90, 92 are complimentarily shaped to fit within therespective first and second alignment holes 81, 83 without allowingsignificant rotational movement (e.g., clocking) of the ramp body 42upon installation of the load/unload ramp assembly 40 onto the baseplate 11. Put another way, upon installation of the load/unload rampassembly 40 onto the base plate 11, the first and second alignment posts90, 92 of the load/unload assembly 40 are disposed within the respectivefirst and second alignment holes 81, 83 of the base plate 11 to preventany significant sliding and/or rotational movement of the load/unloadramp assembly 40 in relation to the base plate 11. Accordingly, each ofthese alignment posts 90, 92 can have a variety of cross-sectionalconfigurations which would enable each of these alignment posts 90, 92to function in preventing rotational movement of the ramp body 42including, but not limited to, circular, elliptical, triangular, andquadrilateral cross-sectional configurations.

Referring now to FIG. 7, the load/unload ramp assembly 40 has beeninstalled on the base plate 11. The shaft 54 of the fastener 52 extendsthrough the fastener aperture 50 between the first and second free ends47, 49, and the head 56 of the fastener 52 exerts a force at least onthe first and second free ends 47, 49. As a result, the first and secondbase plate attachment cantilevers 46, 48 are generally deflected towardthe base plate 11 to forcibly engage the load/unload ramp assembly 40against the base plate 11. In one embodiment, the first and second baseplate attachment cantilevers 46, 48 are driven or deflected intoforcible engagement with the base plate 11 at least at the respectivefirst and second base plate engagement portions 58, 60 of the respectivefirst and second attachment cantilevers 46, 48. In the illustratedembodiment and upon full engagement of the fastener 52, the respectiveupper surfaces 66, 68 of each of the first and second base plateattachment cantilevers 46, 48 is positioned in at least substantiallyhorizontal relation when the load/unload ramp assembly 40 is installedon the base plate 11, although such need not be the case. Prior to theinstallation of the load/unload ramp assembly 40 onto the base plate 11and as noted above, the respective upper surfaces 66, 68 of each of therespective first and second base plate attachment cantilevers 46, 48 maybe at least generally angled upward toward the top surface 41 of theramp body 42; however, the respective first and second base plateattachment cantilevers 46, 48 are bent or deflected down toward to thebottom surface of the ramp body 42 upon tightening of the fastener 52into the fastener receptacle 84 of the boss 82. Other embodiments arecontemplated wherein each of the upper surfaces 66, 68 of the respectivefirst and second base plate attachment cantilevers 46, 48 remainsubstantially coplanar prior to installation, and upon installation,bend downward to exhibit an angle disposed toward the bottom surface 43of the ramp body 42. What is important is that the first and second baseplate attachment cantilevers 46, 48 are deflected at least generallytoward the base plate 11 by the fastener 52, so as to forcibly engagethe load/unload ramp assembly 40 with the base plate 11.

In addition, the lower surfaces 78, 80 of each of the first and secondbase plate attachment cantilevers 46, 48 generally extend at leastgenerally upwardly progressing toward the respective first/second freeend 66, 68 of respective first/second base plate attachment cantilever46, 48. Even after the load/unload ramp assembly 40 has been installedon the base plate 11, a space may exist between at least portions of therespective lower surfaces 78, 80 of the first and second base plateattachment cantilevers 46, 48 and the first surface 13 of the base plate11. However, in the embodiment illustrated in FIG. 7, at least the firstand second base plate engagement portions 58, 60 of the respective firstand second attachment cantilevers 46, 48 are forcibly engaged with thefirst surface 13 of the base plate 11 when the load/unload ramp assembly40 is properly installed on the first surface 13 of the base plate 11.In other embodiments, the first and second base plate attachmentcantilevers (e.g. 46, 48) do not have engagement portions (e.g. 58, 60)which forcibly engage the first surface 13 of the base plate 11. In suchembodiments that lack engagement portions (e.g. 58, 60), the axial forceof the head 56 of the fastener 52 on the upper surfaces 66, 68 of therespective first and second base plate attachment cantilevers 46, 48deflects the first and second base plate attachment cantilevers 46, 48with a sufficient force to fixedly engage the bottom surface 43 of theload/unload ramp assembly 40 against the respective mounting pads 86, 88to secure the load/unload assembly 40 onto the base plate 11.

The shaft 54 of the fastener 52 is threadingly engaged with thecomplimentarily threaded walls 94 of the fastener receptacle 84 of theboss 82 of the base plate 1. Usually, the shaft 54 of the fastener 52 isgenerally moved further within the fastener receptacle 84 until the head56 of the fastener 52 engages an upper surface 85 of the boss 82. Statedanother way, in an installed position, the head 56 of the fastener 52generally has a lower surface 57 which is seated on the upper surface 85of the boss 82 of the base plate 11. In other words, once installed, thelower surface 57 of the fastener head 56 is in directcommunication/engagement with the upper surface 85 of the boss 82 of thebase plate 11, while at the same time engaging the first and second baseplate attachment cantilevers 46, 48.

This fastener (preferably via the lower surface 57 of the head 56) 52generally exerts an axial force within a range of about 25 pounds up toabout 400 pounds, and more preferably about 100 pounds up to about 200pounds, on the upper surface 85 of the boss 82 of the base plate 11. Inaddition to affecting a force on at least the upper surface 85 of theboss 82, the lower surface 57 of the fastener head 56 generally deflectsthe first and second base plate attachment cantilevers 46, 48 whichurges at least portions of the bottom surface 43 of the load/unload rampassembly 40 into forcible engagement with underlying portions of thefirst surface 13 of the base plate 11. This deflection of the first andsecond base plate attachment cantilevers 46, 48 which urges at leastportions of the bottom surface 43 of the load/unload ramp assembly 40into forcible engagement with underlying portions of the base plate 11is generally in response to the shaft 54 of the fastener 52 being movedfurther within the fastener receptacle 84. Accordingly, in an installedposition, the first and second base plate attachment cantilevers 46, 48each generally deflect from about 4 mils to about 8 mils in oneembodiment due to the force exerted by the head 56 of the fastener 52 onthe first and second base plate attachment cantilevers 46, 48.Generally, this axial force exerted on the first and second base plateattachment cantilevers 46, 48 of the load/unload ramp assembly 40 iswithin a range of about 1 pound up to about 10 pounds. Thus, the axialforce which is exerted on the boss 82 of the base plate 11 by thefastener 52 in the fully installed position is generally greater, andpreferably significantly greater, than the axial force which is exertedon each of the first and second base plate attachment cantilevers 46, 48by the fastener 52 in the fully installed position. This significantlyreduces the potential for the fastener 52 retracting out of the fastenerreceptacle 84 over the life of the disk drive 10. Moreover, thissignificantly reduces the load that is applied to the load/unload rampassembly 40 to retain the same on the base plate 11, so as to reduce theeffects of creep that may occur over the life of the disk drive 10.

Those skilled in the art will now see that certain modifications can bemade to the apparatus and methods herein disclosed with respect to theillustrated embodiments, without departing from the spirit of thepresent invention. And while the invention has been described above withrespect to the preferred embodiments, it will be understood that theinvention is adapted to numerous rearrangements, modifications, andalterations, and all such arrangements, modifications, and alterationsare intended to be within the scope of the appended claims.

1. A method of interconnecting a load/unload ramp assembly with a baseplate of a disk drive, the method comprising the steps of: disposingsaid load/unload ramp assembly on said base plate; passing a shaft of afastener through a space past a first free end of a first base plateattachment cantilever of said load/unload ramp assembly and into afastener receptacle on said base plate; moving said shaft further withinsaid fastener receptacle; and deflecting said first base plateattachment cantilever to in turn direct said load/unload ramp assemblyinto forcible engagement with an underlying portion of said base plate.2. A method, as claimed in claim 1, wherein said disposing stepcomprises disposing first and second alignment posts of said load/unloadassembly within first and second alignment holes of said base plate. 3.A method, as claimed in claim 1, wherein said moving step comprisesthreadingly engaging said shaft of said fastener with complimentarilythreaded walls of said fastener receptacle.
 4. A method, as claimed inclaim 1, wherein said deflecting step is responsive to said moving step.5. A method, as claimed in claim 1, wherein said deflecting stepcomprises engaging a head of said fastener against an upper surface ofsaid first base plate attachment cantilever.
 6. A method, as claimed inclaim 1, wherein said base plate comprises a protruding boss, whereinsaid fastener receptacle is disposed within said protruding boss,wherein said moving step is executed until a head of said fastenerengages an upper surface of said boss.
 7. A method, as claimed in claim6, wherein said moving step comprises exerting an axial force on saidprotruding boss that is greater than an axial force exerted on saidfirst base plate attachment cantilever.
 8. A method, as claimed in claim7, wherein said moving step comprises exerting an axial force of about25 pounds up to about 400 pounds on said protruding boss, and whereinsaid deflecting step comprises exerting an axial force of about 1 poundup to about 10 pounds on said first base plate attachment cantilever. 9.A method, as claimed in claim 1, wherein said deflecting step comprisesdeflecting said first base plate attachment cantilever by an amount witha range of about 4 mils to about 8 mils.
 10. A method, as claimed inclaim 1, wherein said passing step further comprises passing said shaftof said fastener through a fastener aperture defined at least in part bysaid first free end of said first base plate attachment cantilever and asecond free end of a second base plate attachment cantilever of saidload/unload ramp assembly, wherein said method further comprises thestep of deflecting said second base plate attachment cantileversimultaneously with said deflecting said first base plate attachmentmember step to in turn direct said load/unload ramp assembly intoforcible engagement with said underlying portion of said base plate.